In order to satisfy the demand of peak spectrum efficiency, support for eight antennas at a base station side is added during formulation of a Long Term Evolution Advanced (LTE-A) standard for a new generation of wireless cellular mobile communication system.
A codebook for eight-antenna is designed by using a codebook for two-antenna and a codebook for four-antenna to produce a Kronecker product, and use the codebook for four-antenna and the codebook for two-antenna to produce a Kronecker product, so as to generate a full rank codebook C/V) for eight-antenna, which is specifically shown in Formula (1):CB8(8)⊂MCB8(8)={W(2)W(4)|W(n)εCBn(n)}∪{W(4)W(2)|W(n)εCBn(n)}  (1)
where
                    w                  (          2          )                    ∈              CB        2                  (          2          )                      =          {                                    1                          2                                ⁡                      [                                                            1                                                  1                                                                              1                                                                      -                    1                                                                        ]                          ,                              1                          2                                ⁡                      [                                                            1                                                  1                                                                              j                                                                      -                    j                                                                        ]                              }        ,n is equal to 2 or 4, W(2) is a codeword in the codebook for two-antenna, W(4) is a codeword in the codebook for four-antenna, CB2(2) is a full rank codebook for two-antenna, and CB4(4) is a full rank codebook for four-antenna. The codeword for eight-antenna does not adapt to characteristics of a dual-polarization channel, and cannot be effectively applied to a dual-polarization antenna.